I have a friend who is into outdoor camping and no stranger to roughing in the wild (he was a commando). He is always raving about visiting Canada and seeing the salmon run and would like to see it this year.
When is a good time of the year to go? Are they are any established trails that my friends can follow?
He should check out the West Coast Trail.
He’s going to have to narrow it down a bit - Canada’s a fairly big place. 
I’m sure there are tourist areas where you can watch the salmon run and hike on trails and camp and stuff - Kamloops tourism might be a place to start. (Don’t let the picture fool you - I’m sure there are a million trails and camping areas around the metropolitan area.)
Well, I guess it’s a “give us your recommendations” thing since neither of us know Canada much at all!
If you can get there, your Commando friend will not be disappointed with a visit to the Yukon, (they hate the ‘the’, but what you gonna do?)
The wilds are truly wild, camping and hiking possibilities to meet every skill set, desire. You will see salmon, and tons of other wildlife besides.
Check out their web page, for more info!
If you’re not interested in going quite that distance, look into British Columbia.
I can promise you will not be disappointed with either choice. Do let us know how it goes, if you make the trip. I, for one, jealously want to hear all about it!
Seconded.
Or you can just basically head to Banff or Jasper National Park. Google them, there is a tons of information online.
Come check out the Parks Canada website. Each park has a mini-site with details about camping, hiking, and other attractions. I favor Forillon National Park myself (ocean views, birdwatching, sea kayaking), but then again I worked on their website years ago Though if you really don’t know much about Canada, I must warn you that the staff in most parks in Quebec have limited English-speaking abilities (mostly French-speakers there).
Outdoor hiking as opposed to the indoor variety? 
Does he have plans on where he’s flying to or starting from? Seriously, it’s a very big country. How much time, what time of year, how long does he want to be away from civilization? Is he looking for dayhikes, overnights, mountaineering, or extended backpacking excursions?
Is he committed to seeing the salmon run? That will limit him to along the coast, and keep him out of the Canadian Rockies which have some amazing scenery and national parks. There are vast areas of the Canadian Rockies in BC and Alberta around 4 interconnected national parks; Banff, Jasper, Kootenay, and Yoho plus several provincial parks that could keep a hiker busy for a lifetime.
Dude, Canada has a million amazing hikes from coast to coast to coast.
Second the parks Canada site. If you’re an East-Coaster, there’s lots of rugged scenary to choose from in the Maritimes.
Ontario has Algonquin Park.
I’m sure Quebec has lots of cool stuff, but I’m not so familiar with them.
Eastern Manitoba is pretty. Northern Saskatchewan has a gazillion lakes.
Alberta has the rockies, especially Banff and Jasper. Don’t forget Kananaskis and Waterton, though.
BC also has the Rockies, but also basically the entire coast and Vancouver Island.
Yukon and NWT has a much shorter ‘tourist’ season, but can be spectacular.
If salmon is important, I think you’ve narrowed your choice to BC. I don’t think the maritimes have salmon runs, but I could be mistaken. The above links should be helpful.
If he’s coming in the high season, you often need to pre-book campsites, so keep that in mind. I was a bit surprised that campsites have web reservation systems, but many do.
Have fun!!!
It’s the second largest country in the world, and has salmon on both the east and west coasts. Where is your friend now?
No salmon fishing here, but check out the Parks in Ontario. Northern Algonquin in August is the closest to heaven on earth IMO. The fishing ain’t bad either.
The Adams River Sockeye run in BC is spectacular, but you almost drive right up to the trails to see the fish. And there’s only about 4-6km of trails. I live an hour west and have going since the early 80’s.
I’ve hiked in Tweedsmuir provincial park (about 100km inland from Bella Coola) it is gorgeous (you can even try to find my Geocache I placed there).
The view from the top of Hunlen falls is breath taking.
MtM
No plans yet, it’s still in the planning phase.
Yah, the salmon run is the big thing for him, I guess.